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SSB Mountain Wave Articles
These articles were written by SSB members and have a wealth of great information on wave flying and particularly local conditions. A must read before flying the local Boulder wave. Print them out.

The 2000K Wave Flight Pt 1 - Dr. Joachim Kuettner
The 2000K Wave Flight Pt 2 - Dr. Joachim Kuettner
Fun Wave Flights - How To - Mark Terry
Flying Wave for the Altitude Diamond - Mark Terry
Some Thoughts About Getting Your Diamond - Colin Barry
Wave Window Tips - Vic Haynes

Fun Wave Flights - How To
Mark Terry

The wave was working very nicely on Wednesday and I made two training flights to 18000' - one from a release at 8000' near the East end of the runway and one two hours later around 2:30 p.m from a height of 10,000' just south of Boulder reservoir.

Both the climbs were made east of the foothills and were started at a relatively low altitude. Since one of the students had a couple of days earlier taken a tow to 15,000' in effort to work the wave and ended up nearly beating the tow plane back to the field I thought it might be helpful to describe Wednesday's wave climbs to give some pointers to those wishing to fly the wave this winter.

First just because some the best looking lennies are located high back on the divide - you don't have to tow back there to contact the wave. In fact a tow straight back into the mountains is quite likely to encounter areas of strong sink and rotor which may force the tow back out of the mountains.

Also it is generally not necessary to stay on tow until the lift goes laminar - which it usually does around 12-14000'. Lift below the laminar layer can be rotor, thermal or generated by shear (this was the case on Wednesday).

When there is workable lift - get off!!

You will gain more experience and more enjoyment by working you way up to the wave than by hanging on to the towplane until the lift goes laminar and your tow bill matches a good night out on the town. Working laminar lift frankly takes little skill apart from matching glider speed and headwind to stay in the up going wave location.

However if you accept the challenge to climb into wave you must have patience. Sometimes you can get off in strong rotor and get a fast wild white-knuckle ride into the wave. At other times like this Wednesday it took about an hour or so to climb into the wave. The best looking lenticulars on this day were located up north-west Hague Pk, Red feather lake area. The clouds over head were 20,000' feet or more. There were almost no clouds below 18,000 and no visible rotor clouds. There was east, south-east winds on the field and a fire near the foothills south of Boulder showed East wind. The climbs were made I believe in a shear layer between the west and east winds. The lift strength varied from 1/2 knot to about 3 knots after passing through 12,000' it became more laminar and once past 14,000 we obtained 6 knots. On the first flight after reaching 16,000 we headed into the hills and found the secondary wave over Jamestown. At that location there was noticeable rotor and climb once it went laminar was 10 knots plus.

On the second flight we had to work very weak lift over Boulder Reservoir from about 8,500 up to about 11,000 before finding stronger lift over Longmont which was worked till 18,000 - going laminar around 14,000'.

We had considerable wind-shear in the pattern on both flights - west at pattern height and east on the ground. In these circumstance make sure you keep your airspeed and don't get fooled by watching groundspeed.

Finally if you think there is a chance of making up into the wave wear something warm - I always seem to end up at 18 wearing a T-shirt and oxygen mask with an enthused student who wants to stay up another two hours.
 

Flying Wave for the Altitude Diamond
By Mark Terry

Wave lift is often described as silky smooth, but to get there you often have to go through very rough air, so rough sometimes that this diamond can aptly described as - 'a diamond in the rough'. I would like to outline the preparation you need to go through to attempt a diamond climb in wave at Boulder, and also use this as an opportunity to describe the procedures that we have in place to use our wave-window - the Araphoe Peak soaring area.

A diamond climb is a climb of 5000 meters, (3.2808 feet/meter) which is 16404 feet. To be sure of obtaining the climb you should at least climb 17,500 off tow on the altimeter. The climb is measured from the low point on the barograph trace (that is any- time after the notch procedure which identifies that you are off tow) to the highest point obtained. You should give yourself a margin of at least 1000' to allow for inaccuracies in altimeter readings, and barograph trace measurement. At Boulder we are already at 5000' and even if we contact wave around 10,000 MSL that will dictate climbing to around 28,000 MSL which means we will have to make use of our wave-window to legally climb above 18000 MSL. Above 18000 MSL you are in positive control airspace Class A and normally you would be on an IFR flight plan and be in radio contact with ATC. Opening the Arapahoe Peak Soaring area (APSA) and maintaining radio contact with Denver ARTCC allows us to fly above 18000 MSL as long as we stay within our designated airspace. So part of our diamond climb attempt at Boulder involves opening APSA and following the agreed procedures. This means reading and signing the letter of agreement between Denver ARTCC and the SSB. A copy is kept in our shack in the checkout box, read and add your name to the attached sheet if you have not already done so. Use of the area will be indicated on our wave- window board located on the outside of the shack. The first person to request use of the APSA will enter details on the board  (time slots, altitude requested). Subsequent potential users will only need to telephone to ARTCC if they want to extend the time parameters, that is why the first request should be for an ample time block (3-4) hours. The board will indicate launch times of other gliders and possibly whether any glider is in the APSA.
 
I include a synopsis of the letter of agreement below- The wave window is controlled airspace that you need to activate for glider use if you intend to fly in wave above 18,000'. You must have radio contact with Denver Center (DARTCC) before you enter the window.  The location of the window is as follows:

40 02'N 105 53'W (1 NM S of Elkdale,CO)
40 08'N 105 53'W (4 NM NE of Grandby,CO)
40 09'N 105 22'W (3 NM NE of Jamestown, CO)
39 58'N 105 14'W (1 NM NW of Marshal, CO)

1.      Call Denver ARTCC Military Coordinator (303 651-4252) at least 30 minutes prior to use. Request use of the Arapahoe Peak soaring area. You will need to specify TIMES at which the airspace will be used and also an initial altitude (ask at least for 30,000'). You need to say which gliders will want to use the window.

2.   Get and confirm Radio frequency typically it will be 128.65

3.      In the air and below 18,000' contact Denver center, say position and altitude and N number and ask to enter the window e.g. "N134BC request clearance into Arapahoe Peak soaring area".

4.    Remain within the released airspace, altitudes and time parameters.

5.    Comply with instructions received from DARTCC while operating above FL180. FL means flight level and this means the altimeter should be set to 29.92.

6.    On leaving and or below 18,000 contact DARTCC and say glider N---- is leaving window.
Maintain a listening watch on assigned radio frequency. In the event of radio failure, aircraft should exit area 'prior' to end of time period. Then on the ground 'immediately' notify DARTCC at 651-4241. That is if you have lost radio contact and were unable to make re-establish radio contact prior to leaving the APSA, you MUST do the telephone call when back on the ground.

7.    The last glider when on the ground should telephone 651-4241 to release the area back to DARTCC and also report the number of sorties into the area (that is the number of gliders that entered the airspace).

This final telephone call to DARTCC should occur before or a short time after the end of the allotted time slot.  

A likely diamond climb scenario might go like this- on arriving at the field, the sky signs look promising, lenticular clouds, rotor clouds maybe also cumulus clouds lined up north-south. We obtain the wave forecast from Denver to give us wind speeds and direction and also potential wave height. We go through our checklists for wave flight- warm clothing - radios (best to have a backup handheld as well as a working ship radio) - oxygen checks  

PRICE - Pressure, Regulator, Indicator, Connections, Emergency (bailout bottle).  

Our wave-ship the 1-34 has a pressure demand system which is good to 40,000', for a diamond climb at Boulder 27,000 will usually be sufficient and you would want to switch to 100% oxygen above 20,000'. For this system to be effective you need a good seal on the mask (part of the PRICE checklist - connections). Prior to this attempt you will need to have had club checkouts wave-rotor, west-wind, oxygen, parachute. Also an altitude chamber ride which among other things will demonstrate signs and dangers of hypoxia (lack of oxygen) - one of which is the insidious effect that nothing at all is wrong and that you feel great.

We make the telephone call to request use of APSA, or we add our name and ship to the wave board if the request has already been made. During the preflight check everything in the ship must be towed and made secure (including you -straps tight) since the rotor will attempt to shake everything loose and you don't need barographs, cameras and handheld radios flying around the cockpit while hang on white-knuckled trying to maintain position on the tow ship. Check security again in the takeoff checks (ABBBCCCDE - altimeter, brakes(open-then shut),ballast as re-quired but bolted in or secure, belts(tight as you can- make sure you can reach radio mike), cable-good (you need a good rope and links for wave/rotor tow), canopy-yes make sure this is shut secure, controls, wind Direction, Emergency plan - what of you do if rope breaks?). Have the oxygen mask on before giving the rudder wag to the tow ship- you don't want to be fiddling with this while trying to climb in rotor. You have two options for the getting into wave (1) let the tow ship take you there this may mean a tow above 12000' (but you will get off before 14000' won't you? the tow pilot does not have oxygen). You may get towed through several rough rotor areas and areas of bad sink before reach the up-going wave, but this is usually the fastest way of getting into the good stuff. A good tow pilot will stay in the lift band to get high before heading west. However you may elect to work the upwind rotor lift to get into the wave layer. This can be exciting, often this takes surprisingly little time however you may also have your brains well and truly beaten out, and conclude it may have been smarter to let the tow plane tow you above this turbulence. Sometimes thermals can also take into the wave, particularly in the summer.

Once off tow and when you have found lift get the notch squared away ; you will need a good notch to mark 'off tow' particlulary if you have been in rough rotor. When you arrive in good wave lift remember you need to maintain position over the ground to prevent being blown downwind and into down-going wave. Often this means 'S' turning, but if the wind is strong fly directly into wind and adjust your speed to stay in the lift band. Typically you will be in the secondary wave and this may go high enough for the diamond climb, but often you will have to leave for the primary wave to obtain the required altitude. Make sure you sufficient altitude before diving for the primary since you will be going through strong sink before contacting the up-going primary wave. Any time when you are in good lift and it appears likely to take you above 18000' you need to contact DARTCC and obtain clearance into the APSA. Sometimes the lift can be tremendous and you need to contact early or you will be holding the ship down with full spoilers (and even that might not be enough).

Once you have been cleared in and are climbing you can try to locate the strongest lift. As you are climbing towards your goal, relax and enjoy the spectacular views this will conserve your oxygen. Normally the diamond climb can be completed under 30,000' MSL. If you elect to go higher above 30,000' be aware that you are taking substantial risks due to the reduced pressure and extreme cold. At these altitudes oxygen has to be forced under pressure into your lungs, by the pressure demand system, in order for you breathe. Your mask must have a good seal for the system to work. TUC (time of useful consciousness) maybe less than a minute, so if your oxygen unit failed you would have to make use of a backup system e.g. the bailout bottle, while descending. In order to descend fast you may need to fly into descending wave. At even higher altitudes your blood boils - dissolved nitrogen forms bubbles which can lodge in your joints and give extreme pain (this is called the bends) and flight in these regions requires a pressure suit or pressurized cockpits. It is also extremely cold at these altitudes and you can risk frostbite. Be aware also the canopy can frost over from the water vapor in your breath. The time I did my diamond I had to chip it away with a credit card. You might try taping a clear plastic sheet to the canopy before the flight which I am told works.

Lets assume you complete the climb and want to descend - the best method is turn downwind and find the down going wave. At all times keep an eye on the clouds to make sure you have ground contact. You will want to have practiced the Benign Spiral just in case a descent through clouds becomes inevitable. In our Grobs this means trimming for about 60 knots, full spoilers and taking hands and feet off the controls - the ship will enter a gentle spiral which is stable. Trying to fly the ship with no visual references will typically end in a unhealthy high speed vicious spiral. However, as long the glider pilot is alert no such emergency procedures will be necessary but you should know how just in case. As the descent continues below 18000' MSL you need to contact Denver ARTCC to tell them you are leaving the airspace. (If you cannot contact them you must telephone once in the ground.) At this time call the field to find out winds, of-ten there will be a brisk west wind waiting to make the landing interesting.

Once you are on the ground update the wave-board and if you are the last glider (nobody else signed up on the board) then you should telephone and report which gliders are down. As long as everyone uses the wave-board correctly then communications with DARTCC can be accurate. The last operation is to enter details of your flight in the wave-book kept in the shack. With good preparation and on the right day a diamond climb in the wave can be a blast.


Some Thoughts About Getting Your Diamond
by Colin Barry

Colin Barry’s thoughts after his diamond height gain flight. 

1. Be prepared, have the clothing you will wear in a bag in the back of your car.
2. If it looks like a wave day phone Denver Center as soon as you get to the field to request the wave window. Pick an appropriate time for it to open. You can figure on:

• 45 minutes to get the glider/barograph ready (Does not include O2 fill).

• 20 minutes on tow

• 20 minutes to get to 17,000 ft (if your lucky) when you should call to request entry to the wave windows.

1. Request at least 30,000 ft. You need 16,404 ft for your diamond so check with the locals at what height they are contacting the wave.
2. Visit the bathroom before the flight. You will experience cold temperatures and this may affect your bladder.
3. I recommend a layered approach to your clothing. I especially recommend a set of "Long John" underwear and a wooly hat. Be careful that the clothing you choose is not so bulky that it inhibits your ability to pilot the aircraft.
4. Secure all loose items in the cockpit, including yourself, prior to take off.
5. You've gone to a lot of trouble for this flight so make sure you are confident of climbing before your release.
6. Establish yourself in the lift and notch the barograph noting your height. Use this to calculate the target altitude you need for your diamond. You may want to write this down as you may forget in the excitement of climbing in the rotor.
7. The higher you get the more difficult it is to maintain position in the lift using visual reference. A GPS with a moving map and ground speed display is of great benefit in locating the "hot spots".
8. You may find the inside of the canopy starts to ice up because of the moisture in your breath. Open all the windows and vents before this starts happening… You did dress warm didn't you? You can also try staying out in the sun rather than under the cloud cover.
9. Monitor your O2 supply at all times. Make sure your mask is a tight fit. You may find moisture bleeding through the sides of your mask and fogging up your glasses.
10. Be aware of your symptoms for hypoxia. Take immediate action if you notice them occurring.